The Role of VP16 in the Life Cycle of Alphaherpesviruses

The protein encoded by the UL48 gene of alphaherpesvirus is named VP16 or alpha-gene transactivating factor (α-TIF). In the early stage of viral replication, VP16 is an important transactivator that can activate the transcription of viral immediate-early genes; and in the late stage of viral replication, VP16 as a tegument is involved in viral assembly. This review will explain the mechanism of VP16 as α-TIF to activate the transcription of viral immediate-early genes, transition from viral latency to reactivation, and effects on viral assembly and maturation. In addition, this review also provides new insights for further research on the life cycle of alphaherpesvirus and the role of VP16 in the life cycle of the virus.